1. Field of the Invention
The present invention relates to a chuck device. More specifically, the present invention relates to a chuck device with a plurality of gear mechanisms which increase a rotational drive force applied through an input member.
2. Description of the Related Art
Conventionally, in machine tools, a chuck device secures a work piece or tool to a work surface. Work surfaces may include a table, a work pallet, or a principal axis clamp. Such chucking devices typically include a base member, secured to the work surface, and a claw member movably mounted on the base member.
Conventional claw members are movable to allow the work piece or tool to be xe2x80x98chuckedxe2x80x99 or secured in the chuck device. Chuck devices may include one, two, or three claw members.
Referring now to FIG. 9, a chuck device 100, secures a work piece Wa. Chuck device 100 includes a base member 101. An input shaft member 103 extends from inside base member 101 to project from a side opposite a claw member 102. Chuck device 100 also includes a conversion mechanism 104 and a hydraulic cylinder (not shown).
A leg 102a, of claw member 102, slidably engages a T-shaped groove 101a formed on base member 101. An outer end of input shaft 103 connects to the hydraulic cylinder (not shown).
Conversion mechanism 104 includes a conversion member 105 secured to input shaft member 103. Conversion member 105 includes a sloped engagement groove 105a thereon. Sloped engagement groove 105a has a T-shaped cross-section and is sloped relative to the direction of motion of claw member 102. An engagement section 102b on claw member 102 slidably engages sloped engagement groove 105a. 
During operation, the hydraulic cylinder (not shown) drives input shaft member 103 and conversion member 105 in an axial direction. The resulting axial drive force is redirected by conversion mechanism 104. After redirection, the axial drive force is transferred to claw member 102, causing claw member 102 to move in the direction of an arrow a
Referring now to FIG. 10, a chuck device 110 implemented by the present applicants includes a base member 111, a claw member 112, and an input member 113. Chuck device 110 also includes a conversion mechanism 114.
A leg 112a, on claw member 112, slidably engages a T-shaped groove 111a formed on base member 111. Input member 113, formed as a bolt, is screwed into base member 111. During operation, a rotational drive force is manually applied to input member 113, using a handle or other manual rotation tool 119, to tighten or loosen chuck device 110.
Conversion mechanism 114 includes a conversion member 115 which receives and engages a head of a shaft of input member 113. A sloped surface 115a on conversion member 115 is sloped relative to a direction of movement of claw member 112. A sloped surface 112b on claw member 112 is in planar contact with sloped surface 115a. 
A compression spring 116 elastically biases claw member 112 toward input member 113.
During operation, when input member 113 is rotated in a tightening direction, conversion member 115 is driven downward into base member 111 to force claw member 112 in the direction of an arrow b, thus securing a work piece Wb. When input member 113 is rotated in a loosening direction, the biasing force of compression spring 116 urges claw member 112 to move in the releasing direction of an arrow c to release work piece Wb.
In conventional chuck devices, drive force applied through an input member is marginally increased (multiplied) to drive claw members. Unfortunately, any increase in drive force applied through the input member is limited by the sloped engagement grooves and sloped surfaces used in a conversion mechanism. This is a physical and design limitation which makes it difficult to provide a high force (since there is a lack of a multiplication rate) to increase the ratio to grip a work piece. As a result, in manually driven chuck devices, it is difficult to chuck a work piece or tool firmly. Failure to firmly chuck a work piece or tool may lead to reduced machining precision and damage to cutting tools. Manual operation may result in reduced ease of use and lower production efficiency. Repetitive manual chucking may lead to physically fatigued operators thus increasing safety risks and extending chucking time. In sum, manual chucking operations reduce productivity.
Unfortunately, where an automatic chuck devices drives the input member, the actuator makes the chuck device larger. The increase in size, increases production costs, production risks, and reduces productivity.
Increasing the slopes of the sloped engagement groove can improve the rate at which the drive force is increased. Unfortunately, the ratio of the displacement of a claw member to a displacement of the conversion member is very small. This ratio limits the size of the work piece or tool that can be chucked, thus further reducing operational versatility.
An object of the present invention is to provide a chuck device that improves and increases a rate of applied drive force.
Another object of the present invention is to provide a chuck device that improves usability and increases the efficiency and force of chucking operations.
Another object of the present invention is to provide a chuck device that is compact.
Another object of the present invention is to provide a highly versatile chuck device, easily adaptable to multiple production environments.
It is another object of the present invention to provide a chuck device that is readily adaptable to one or two claw embodiments, stationary or mobile embodiments, and flat, tilted, or multi-axial positions.
The present invention relates to a chuck device including a first worm gear mechanism linked to a second worm wheel mechanism which operate in tandem to receive, increase, and redirect an input rotational drive force. A conversion mechanism receives and further augments the drive force from the second worm gear mechanism and converts the drive force into an axial force. The conversion mechanism transfers the axial force symmetrically to a pair of claw members. The claw members move relative to each other and firmly secure a work item to the chuck device.
According to an embodiment of the present invention, there is provided a chuck device comprising: a first base member, a second base member on the first base member, first means for receiving and increasing a rotational force, the first means for receiving and increasing in the first base member, second means for receiving the rotational force from the first means and for further increasing the rotational force into an increased rotational force, the second means for receiving in the first base member, the second means for receiving effective to redirect the increased rotational force perpendicular to the first means for receiving and increasing, means for converting the increased rotational force from the second means into an increased axial force perpendicular to the first and the second means, and the means for converting operable between the first and the second base member, whereby the rotational force is transferred through the first base member to the second base member and converted into an increased axial force operable relative to the second base member.
According to another embodiment of the present invention there is provided a chuck device, further comprising: means for chucking an external item in the second base member, and the means for chucking receiving the increased axial force and securely chucking the external item to the second base member, whereby the external item is easily secured with a holding force magnified from the rotational force.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first conversion member in the means for converting, the second means for receiving effective to drive the first conversion member away from the first means for receiving and increasing, at least a first sloped engagement groove on the first conversion member, at least a first claw member in the means for chucking, at least a first engagement section on the first claw member, the first sloped engagement groove sloped relative to a first direction of motion of the first claw member relative to the second base member, the means for chucking effective to operate the at least first claw member axially along an axial direction of the second base member, and the first sloped engagement groove engaging the first engagement section effective to retain the first engagement section and to drive the first engagement section in the first direction of motion and fix the external item to the second base member, whereby the external item is secured to the chuck device.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first worm gear in the first means for receiving and increasing, at least a second worm wheel in the second means for receiving and for further increasing, the rotational force operable about a first diameter, the first worm gear having a first rotational axis and a second diameter, the second diameter greater than the first diameter, the second worm wheel having a second rotation axis, the first rotational axis perpendicular to the second rotational axis, and the first worm gear threadably engaging the second worm wheel and effective to magnifying the rotational force.
According to another embodiment of the present invention there is provided a chuck device, further comprising: a first operational axis on the means for converting, the first operation axis parallel the second rotational axis, the first operational axis perpendicular the an axial direction of motion of the first claw member, the first operational axis perpendicular to the first rotational axis, the first sloped engagement groove sloped relative to first operation axis, and the means for converting effective to receive the increased rotational force and operate along the second rotational axis, whereby the first claw member operates simultaneously in the first direction of motion relative to the second base member and the along the first sloped engagement groove relative to the first conversion member.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first engagement groove in the second base member, at least a first leg on first claw member, the first leg in the first engagement groove, and the first engagement groove effective to engage the first leg and operate the first claw member axially along the first direction of motion.
According to another embodiment of the present invention there is provided a chuck device, wherein: the first sloped engagement groove has a slope on or about 70 degrees relative to a direction of motion of the first claw member.
According to another embodiment of the present invention there is provided a chuck device, wherein: the first base member includes at least a first hole and a second hole, the first worm gear in the first hole, the second worm wheel in the second hole, at least a first cover, the first cover on at least a first face of the first base member, the at least first cover effective to operably retain the first worm gear in the first hole and allow external input of the rotational force, at least a second cover, the second cover on a second face of the first base member opposite, the first face perpendicular to the second face, and the at least second cover effective to operably retain the second worm wheel in the second hole and allow operation of the conversion member relative to the worm wheel.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first grease access in the at least first claw member, the first grease access parallel the first direction of motion, and the first grease access operable along a first face of the first sloped engagement groove, whereby an external lubricant is easily applied between the conversion member and the first engagement section effective to allow smooth operation of the chuck device.
According to another embodiment of the present invention there is provided a chuck device, further comprising: a second sloped engagement groove on the first conversion member, a second claw member in the means for chucking, at least a second engagement section on the second claw member, the second sloped engagement groove sloped relative to a second direction of motion of the second claw member relative to the second base member, the means for chucking effective to operate the second claw member axially along the axial direction of the second base member, and the second sloped engagement groove engaging the second engagement section effective to retain the second engagement section and drive the second engagement section along the second direction of motion and fix the external item to the second base member, whereby the external item is secured to the chuck device.
According to another embodiment of the present invention there is provided a chuck device, comprising: a first base member, a second base member on the first base member, first means for receiving and increasing a rotational force, the first means for receiving and increasing in the first base member, second means for receiving the rotational force from the first means and for further increasing the rotational force into an increased rotational force, the second means for receiving in the first base member, the second means for receiving effective to redirect the increased rotational force perpendicular to the first means for receiving and increasing, means for converting the increased rotational force from the second means into an increased axial force perpendicular the first and the second means, the means for converting operable between the first and the second base member, whereby the rotational force is transferred through the first base member and into the second base member and converted into an increased axial force operable relative to the second base member, means for chucking an external item in the second base member, the means for chucking receiving the increased axial force and securely chucking the external item to the second base member, whereby the external item is easily secured with a holding force magnified from the rotational force, at least a first conversion member in the means for converting, the second means for receiving effective to drive the first conversion member away from the first means for receiving and increasing, at least a first sloped engagement groove on the first conversion member, at least a first claw member in the means for chucking, at least a first engagement section on the first claw member, the first sloped engagement groove sloped relative to a first direction of motion of the first claw member relative to the second base member, the means for chucking effective to operate the at least first claw member axially along an axial direction of the second base member, and the first sloped engagement groove engaging the first engagement section effective to retain the first engagement section and to drive the first engagement section in the first direction of motion and fix the external item to the second base member, whereby the external item is secured to the chuck device.
According to another embodiment of the present invention there is provided a chuck device, comprising: first means for receiving and increasing a rotational force, second means for receiving and increasing the rotational force from the first means and outputting an increased rotational force, the second means for receiving redirecting and rotational force from a first base member to a second base member, means for receiving and converting the increased rotational force from the second means into an increased axial force, means for chucking an external item to the second base member, and the means for chucking receiving the increased axial force and securing the external item to the second base member and the chuck device.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first conversion member in the means for receiving and converting, at least a first sloped engagement groove on the first conversion member, at least a first claw member in the means for chucking, at least a first engagement section on the first claw member, the first sloped engagement groove sloped relative to a direction of motion of the first claw member, the means for chucking effective to operate the at least first claw member axially along an axial direction of the second base member, and the first sloped engagement groove engaging the first engagement section effective to drive the first engagement section in the direction of motion and fix the work item in the second base member, whereby the work item is secured in the chuck device.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least a first worm gear in the first means for receiving and increasing, at least a second worm wheel in the second means for receiving and increasing, the first worm gear having a first rotational axis, the second worm wheel having a second rotation axis, the first rotational axis perpendicular to the second rotational axis, and the first worm gear operably threadably engaging the second worm and magnifying the rotational force.
According to another embodiment of the present invention there is provided a chuck device, including a first base member and at least a first claw member movably mounted on the first base member, for chucking an external item by moving the first claw member, the chuck device comprising: a first input member for receiving and applying a rotational force, a first gear mechanism effective to receive and increase the rotational force, a second gear mechanism effective to receive the rotational force from the first gear mechanism, increase the rotational force, and operate a screw shaft member along an axial direction perpendicular to the first input member, and a conversion mechanism effective to receive the rotational force, resist rotation relative to the first input member, and convert the rotational force into an axial force to drive the at least first claw member in an axial direction relative the first base member, whereby the chuck device securely engages the external item.
According to another embodiment of the present invention there is provided a chuck device, further comprising: a worm gear in the first gear mechanism, a worm wheel in the second gear mechanism, the worm gear rotating integrally with the input member, the worm gear threadably engaging and the worm wheel, the second gear mechanism including a threaded hole concentric with a center of the worm wheel, and a screw shaft member threadably engaging the threaded hole.
According to another embodiment of the present invention there is provided a chuck device, wherein: the conversion mechanism includes a conversion member, the conversion member secured to the screw shaft member and at least a first sloped engagement groove on the conversion member, the first sloped engagement groove sloped relative to a direction of motion of the first claw member, at least a first engagement section on the first claw member, and the first engagement section slidably engaging the first sloped engagement groove and preventing the conversion member from rotating relative to the worm wheel.
According to another embodiment of the present invention there is provided a chuck device, further comprising: at least the first and a second claw member, the first and the second claw members disposed facing each other on the base member, a first leg on the first claw member, a second leg on the second claw member, the first and the second legs slidably engaging a shared engagement groove on the base member effective to axially align the first and the second claw members, at least a second sloped engagement groove on the conversion member, the second sloped engagement groove sloped relative to a direction of motion of the second claw member, at least a second engagement section on the second claw member, the second engagement section slidably engaging the second sloped engagement groove and preventing the conversion member from rotating relative to the worm wheel, and the conversion mechanism effective to slidably engage and move the first and the second claw member symmetrically along the shared engagement groove.
The present invention provides a chuck device for chucking a workpiece or a tool by moving single or multiple claw members. The chuck device includes a base member and at least one claw member movably mounted on the base member. The chuck device also includes an input member for applying a rotational drive force, a gear mechanism using a rotational drive force applied through the input member to drive a screw shaft member in an axial direction, and a conversion mechanism redirecting an axial drive force transferred through the screw shaft member and driving a claw member.
The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings, in which like reference numerals designate the same elements.